Boiler plant



July 28, 1925. 7 1,547,549

N. F. F; ANDERSSON- BOILER PLANT Filed Sept. 19, 1922 Patented July 2 8, 1925 UNITED STATES 1,547,542) PATENT QFFICE.

NILS FREDRIK FILEMON ANDERSSON, OF STOGKHOLM, SWEDEN, ASSIGNOR 'H) .AK'IIE- BOLAGE'I' LJ'UNGSTRGMS ANGT'U'RBIN, 0F STOCKHOLM, SWEDEN, A. CORPORATION.

BOILER PLANT.

Application filed September 19, 1922. SerialNo. 589,213.

To all whom it may concern:

Be it known that I, NILs FREDRIK FILE- MON ANnuRssoN, a subject of the King of Sweden, residing at 70 Riddaregatan, Stockholm, Sweden, have invented certain new and useful Improvements in Boiler Plants, of which the following is a specification.

In plants with tubular boilers, it is previously known to utilize the heat of the waste gases in an air-preheater disposed above the boiler, such preheater being then of the rotating and regenerative type. Such boiler plants have occupied much space, and they have been difiicult to fire up, which drawbacks have been conditioned partly by the character of the boiler as a tubular one, but partly also by the place of the air-preheater, in that the latter has often been arranged in front of and over the boiler in the space above the stokers place. In existing boiler plants without an air-preheating system, it has often been diflicult to arrange a preheating plant in the immediate proxiniity of the boiler, in that space has not been available for such purpose.

The object of the present invention is to remove these drawbacks by the arrangement of an air-preheating plant in an otherwise unutilized space, and the invention is principally characterized by the combination of a tubular boiler with one or more air-preheaters of therotating and regenerative type mounted underneath the boiler.

The air-preheater is then preferably placed between the ash pit and the lower part of the chimney, the passages for the waste gases and the air for combustion being thereby short, which, evidently, is a favorable feature.

The accompanying drawing illustrates diagrammatically a section through a portion of a boiler house arranged according to the invention, in which boiler house a water tube boiler is built together with a regenerative rotating air-preheater.

In the drawing, 1 designates the outer wall of the boiler house, while 2 is the roof thereof and 3 the space in front of the boiler furnace 4. The bricking-in of the boiler plant is shown in section, the boiler being denoted by 5, whereas the water tubes disposed beneath the boiler and co-operating therewith in known manner are designated by 6.

The drawing illustrates an automatic firing device consisting of a chain grate 7 from which the waste gases pass about the Water tubes 6 in the direction of the arrow 8. In water tube boilers previously known, the waste gases have been passed directly to the chimney 10 through the channel 9 and past the damper 11 shown as closed in the drawing. On the other hand, the waste gases are conducted, according to the invention, in the direction of the arrow 12 through a rotating regenerative air-preheater 13 of the type heretofore known to the chimney 10 through the channel 14, while the air for combustion is conducted to the furnace 4 from the space 15 about the regenerative air-preheater, through which the air passes in the direction of the arrow 16 to the furnace 4 underneath the grate 7. Mounted in the path of the air for combustion and the waste gases are various dampers 17, 18, to regulate the gas and air currents respectively. This control may also be carried out in such manner that the boiler can be fired without the use of the regenerative air-preheater, the dampers 17 and 18 being then closed and the damper 11 opened, so that the waste gases may escape directly to the chimney.

The walls of the passages conducting the hot gases and the air to and from the preheater are preferably bricked in connection with the bricking-in of the boiler.

The space in which the air-preheater is mounted is always present in the type of boiler plant in question, but heretofore it has not been utilized in any way save for its having occasionally been used as a collecting place for the slag and the ashes falling down from the grate. In the boiler plant shown in the drawing, ashes and slag are collected at 20.

According to the present invention, an otherwise unutilized space may thus be employed in a most expedient way by the arrangement therein of an air-preheater of the regenerative rotating type.

By reason of the above-mentioned mounting of the regenerator between the ash pit 20 and the lower part 10 of the chimney, it is also possible to take the air, which has to be preheated and conducted to the furnace, from a place where the temperature is always comparatively high, whereby a higher efficiency is obtained for the plant.

1. A boiler plant, comprising in combination a water tube boiler, and a furnace including ash pit and chimney, an air-preheater comprising a regenerative element having passages therein, means .for imparting rotation to said element and means for causing air and flue gases to pass through said element alternately through the same passages, said air-preheater being placed underneath the boiler tubes between the ash pit and the lower part of the chimney, means for conducting the hot flue gases from' the furnace to and through the air-preheater and means for conducting the preheated air "from the air-preheater to the furnace.

2. A boiler plant, comprising in combina tion a water tube boiler, and a furnace including ash pit and chimney, and air-preheater comprising a regenerative element having passages therein, means for impart ingrotation to said element and means for causing air and flue gases to pass through said e ement alternately through the same passages, said air-preheater being laced underneath the boiler tubes between t e ash pit and the lower part of the chimney, passages for conducting the hot flue gases from the furnace to and through the air-preheater, a passage for conducting the pre.

heated air from the air-preheater to the furnace and dampers inserted in said pas' sages to regulate the gas and air currents respectivel p 3, A boi er plant, comprising in combination a water tube boiler, and a furnace including ash pit and chimney, an air-premheat er comprising a. regenerative element havlng passages therein, means for imparting rotation to said element and means for causin air and flue gases to pass through said e ement alternately through the same passages, said air-preheater being laced underneath the boiler tubes between t e ash pit and the lower part of the chimney, passages for conducting the hot flue gases from the furnace to and through the air-preheater, a passage for conductingthe preheated air from the air-preheater to the furnace and dampers inserted in said passages to regulate the gas and air currents respectively and to set the air-preheater out of function.

4. A boiler plant, comprising in combination a water tube boiler, and a furnace including ash pit and chimney, an air-preheater comprising a regenerative material, means for imparting a rotation to said material and means for causing air and flue gases to pass through said material alternately through the same passages thereof, said air preheater being placed underneath the boiler tubes between the ash pit and the lower part of the chimney, means for conducting the hot flue ases from the furnace to and through the air-preheater, a channel for conducting the "preheated air to the furnace, and aspartition wall separating said channel from the ash pit.

5. A boiler'plant, comprising in combination a water tube boiler,.and a furnace including ash pit and chimney, an air-preheater comprising a regenerative material, means for imparting a rotation to said material and means for causing air and flue gases to pass through said material alternately through the same assages thereof, said air-preheater being p aced underneath the boiler tubes between the ash pit and the lower part of the chimney, a passage for conducting the hot flue gases from the furnace to the air-preheater, a passage for conducting the flue gases from the air-preheater into the chimney, a passage for conducting the pre-heated air from the airpreheater to the furnace and a partition wall separating the inlet passage of the flue gases from the outlet passage of the air, said wall being made in one piece with the fire bridge. p

In testimony whereof Iaflix my signature in presence of two witnesses.

NILS FREDRIK FILEMON ANDERSSON.

Witnesses: w

L, BERG VON LINDE, ERIC HALGER. 

